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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
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    <title>Document</title>
    <style>
        .city {
            float: left;
            margin: 5px;
            padding: 15px;
            width: 300px;
            height: 300px;
            border: 1px solid black;
        }
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</head>

<body>
    <h1>响应式设计</h1>
    <h2>今天下雨了</h2>
    <br>

    <div class="city">
        <h2>第一个</h2>
        <p>第一个大</p>
        <p>说点什么呢</p>
    </div>

    <div class="city">
        <h2>第二个</h2>
        <p>第二个小</p>
    </div>

    <div class="city">
        <h2>第三个</h2>
        <p>随着内容...</p>
    </div>

</body>
</body>

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